Download the chromedriver version based on the chrome version (flutter#9)

* Download the chromedriver version based on the chrome version

* fix webdriver

Author: jakemac53

.travis.yml

@@ -26,7 +26,9 @@ before_install:
   - sh -e /etc/init.d/xvfb start
 
 before_script:
-  - wget http://chromedriver.storage.googleapis.com/2.46/chromedriver_linux64.zip
+  - "export CHROME_LATEST_VERSION=$(/usr/bin/google-chrome --version | cut -d' ' -f3 | cut -d'.' -f1)"
+  - "export CHROME_DRIVER_VERSION=$(wget -qO- https://chromedriver.storage.googleapis.com/LATEST_RELEASE_$CHROME_LATEST_VERSION)"
+  - "wget https://chromedriver.storage.googleapis.com/$CHROME_DRIVER_VERSION/chromedriver_linux64.zip"
   - unzip chromedriver_linux64.zip
   - export PATH=$PATH:$PWD
   - ./tool/travis-setup.sh

pubspec.yaml

@@ -22,4 +22,4 @@ dependencies:
 dev_dependencies:
   shelf_static: ^0.2.8
   test: ^1.5.3
-  webdriver: ^2.0.0
+  webdriver: ^2.1.0

test/sse_test.dart

@@ -41,11 +41,13 @@ void main() {
             listDirectories: true, defaultDocument: 'index.html'));
 
     server = await io.serve(cascade.handler, 'localhost', 0);
-    webdriver = await createDriver(desired: {
-      'chromeOptions': {
-        'args': ['--headless']
-      }
-    });
+    var capabilities = Capabilities.chrome
+      ..addAll({
+        Capabilities.chromeOptions: {
+          'args': ['--headless']
+        }
+      });
+    webdriver = await createDriver(desired: capabilities);
   });
 
   tearDown(() async {